Meanwhile....... back on SYS (the V8 powered Lotus shell)....
Although it had earlier become clear that a certain amount of shell surgery and modification would be needed to install the BMW M62 V8 and the 6-speed M5 Getrag gearbox, it was still my intention to keep the altered aread looking as close to being 'factory original' as possible. So far I am fairly happy with the bulkhead and heater plenum modifications, but just wasn't with the new gearbox tunnel I had made.
On the stock Sunbeam Lotus shells the original gearbox tunnel has already been cut out and replaced with a larger version specifically to cover the ZF gearbox as fitted to this version of the car. In short, not only are many of these factory mods not particularly well carried out, but the new pressing itself leaves a lot to be desired.
After removing the original 'lotus' transmission tunnel, I had previously set about copying it fairly closely in fresh sheet steel and in a single piece as the original was. This resulted in what you see in the photo below.
Firstly, although it is actually quite a short gearbox, the M5 Getrag is both taller and wider still than the original ZF 'motorsport' gearbox it was to replace. In trying to copy the 'Lotus' tunnel, I had also made it quite square cornered, and I just wasn't keen on its appearance like thiswith the bigger gearbox.
Secondly, as the whole gearbox by necessity has to sit a little bit higher up in the car, the transmission tunnel has to be lifted slightly all the way back to the centre of the shell for propshaft clearance anyway.
What really made me reject this Version 1 replacement tunnel though was than on a dummy/ trial fit of the front seats it didn't allow much/ enough clearance for the squabs to be positioned exactly where I wanted them either.
It just wouldn't do and wasn't nearly good enough. Why closely copy something that is already substandard/ poorly done anyway?
.....Cut it all back out again......
.....including the complete top of the propshaft tunnel....
With Version 2 I wanted to keep the tunnel much neater and more closely fitting to the shape of the gearbox casings, allowing just enough space for normal movement.
First then I set about enclosing the bellhousing area and tying it back to the new bulkhead,which I decided was best done in three sections....
After welding these first parts up and linishing them back I set about recreating something similar to the factory stiffening pressing...
.....which was also tacked onto the back of the bellhousing area....
...before forming another piece of sheet into the approximate curvature needed to enclose the main gearbox section...
....then trimming, adjusting and tacking it in place...
....and set about further adjusting its shape and cutting a rectangular hole in it so that just like Version 1 would, it would also accept a standard Sunbeam Lotus gearlever gaiter...
Next a pair of long thin triangular pieces of sheet steel were cut to space the top of the rear section of the tunnel upwards above the propshaft...
...welded into place, and then the original upper piece could be refitted complete with the handbrake mounting...
.....and after linishing....
Wanting to keep as close to a stock in-cabin appearance as possible, it was now time to dummy fit the dash crashroll so that the factory centre console could be offered up. The centre console is made in two halfs, both of which required alteration.
The lower half had to be severely altered to fit over the larger transmission tunnel....
....and the upper half had to have the area around the gearlever gaiter cut away...
The result is that the centre console and the front seats now all fit much better in the cabin despite the much larger gearbox....
There has been a bit more progress on the pedal box, but I think that is enough of an update for tonight!
Here is a final photo of the engine and gearbox in the car, now with its new bulkhead and transmission tunnel largely complete...
Jim